1. Field of the Invention
The present invention relates to surgery. More particularly, the present invention relates to plating systems and tools, and specifically plating systems and tools for treatment of periarticular fractures.
2. State of the Art
Fractures around implants pose unique fixation challenges. The original placement of the implant may predispose the bone to later fracture, as the long-term presence of the implant may change the structure of the surrounding bone and increase susceptibility to fracture. In addition, the implant itself may interfere with healing or the placement of other fixation devices.
This is particularly a problem around the femur where a femoral component of a hip replacement prosthesis may be implanted. Further, as the population ages and the indications for joint replacement increase, the number of implants in the femur is increasing. With increased hip joint replacement, the number of fractures associated therewith has also increased. Once a fracture occurs, treatment is complicated by osteoporosis, defects in the bone, and the presence of the implant. In particular, stems, rods, screws, and methylmethacrylate may block the medullary canal, preventing intramedullary fixation of fractures. Stems and rods also block screw fixation through the medullary canal to hold fracture stabilization plates on bone. The techniques for treating periprosthetic fractures are generally more difficult, with limited options.
Nevertheless, essentially all periprosthetic fractures require some treatment. Stable nondisplaced fractures may only require protected weight-bearing or cast/brace immobilization. However, most unstable periprosthetic implant fractures require surgical stabilization and/or implant replacement to restore function.
Surgical stabilization includes plating to secure the adjacent sections of the fractured bone to facilitate healing, which may occur with or without implant replacement.
It must be appreciated that standard plating includes attaching a stabilization plate to the bone with screws. Given the inability to pass a screw bicortically through the bone and the overall poor quality of the bone, alternative means of fixation are used to couple the plate to the bone. Most typically, such fixation includes unicortical screws that are inserted into the bone in a spatial distribution that does not interfere with the implant and cerclage cables that are wrapped under tension around the bone. The ends of the cable are crimped together with a crimp to maintain tension on the cable at a specific force. However, current tools for working with securing the cable make application of the system difficult. In particular, existing cable tensioners require a temporary tension holder as well as a separate cable tensioner, and both instruments must be operated together and used to tension the cable. In addition, after tension is applied and fixed to the cable, even a small amount of movement between the cable, the plate and the anatomy can cause significant reduction in tension on the cable and release of compression between the plate and the bone.